Sheet metal bending brake



6 Sheets-Sheet l Sept. 8, 1953 R. E. SMITH, sR

SHEET METAL BENDING BRAKE Filed Aug. 9, 1950 Sept. 8, 1953 R. E. sMn-H, sR

SHEET METAL BENDING BRAKE 6 Sheets-Sheet 2 Filed Aug. 9, 1950 INVENTOR. I yay/zo/adS/nzf ATTE R N EYS Sept. 8, 1953 R. E. SMITH, sR 2,651,349

SHEET METAL BENDING BRAKE Filed Aug. 9, 1950 6 Sheets-Sheet 3 ATTD R N EYS Sept. 8, 1953 R. E. SMITH, sR

SHEET METAL BENDING BRAKE s sheets-'sheet 4 Filed Aug. 9. 1950 I N VEN TOR.

ATI'D R N EYS Sept. 8, 1953 R. E. SMITH, sR

SHEET METAL BENDING BRAKE 6 Sheets-Sheet 5 Filed Aug. 9. 1950 ATI'CI R N EYS lSept 8, 1953 l R. E. sMn-H, sR 2,651,349 sEEET METAL BENDING BRAKE Filed Aug. 9, 1950 6 Sheets-Sheet 6 y INVENTOR RAYMOND E. SMITH, SR.

- ATTORNEYS Patented Sept'. 8, 1953 UNITED sTATEs PATENT oEErcE 2,651,349 SHEET METAL BENDING BRAKE Raymond E. Smith, Sr., Waukegan, Ill. Application August 9, 1950, Serial N o. 178,381

7 Claims.

This invention relates to a new and improved tool for bending sheet metal, plate or bars to various angles of bend and with various corner radii of bend. It is particularly adapted to bending narrow folds and anges to 180 degrees (plus) in one operation after the material has been positioned between a mandrel and two anvils. toa plate or sheet bending tool havlng a stationary anvil `with an auxiliary anvil and a swingable mandrel, whereby with a plate positioned upon the anvils the mandrel isbrought to an operative position above the plate and the upwardly bent section or edge of `sheet lor plate is bent over lwith the mandrel turning at onehalf the pace of the auxiliary anvil to vsuch a position whereas the mandrel is caused to be withdrawn automatically and wherein the auX- iliary anvil bends the edge of the plate downwardly to a position substantially parallel to the body of the plate.

In this invention the mandrel is unlike the conventional brake or bending tool in that it is swingable upon a common axis with the auxiliary anvil and connectedby a novel linkage to both anvils in a precalculated manner so that the mandrel moves at one-half the'pace of the auxiliary anvil whereby at all times the center line of the mandrel bisects the angle formed by the top surfaces of the opposing anvils and maintains this direct relation up to a certain point whereas the mandrel is made to automatically retirefrom the forming operation and the two anvils complete the bend without assistance of the'mandrel.

` In the usual type of sheet metal brake or plate bending tool it is difficult to form the edge of the material through an angle of 180 degrees without repositioning the material in the machine and this requires set up time which is not only costly but multiplies the possibility of making mistakes. With this thought in mind` this invention vcontemplates a sheet metal bending tool in which a movable part of an anvil and a mandrel are pivotally mounted on the frame'in which a stationary anvil is positioned and in which means is provided for actuating the mandrel as the bending section of the anvil is actuated.

The object of this invention is, therefore, to provide means for forming an improved plate bending tool whereby cleats, hems and the like, are completely formed on. the edges of plates in .repeatl Y production.

Another object of the invention provides for simple 'and positive adjustment between the mandrel and anvil surfacesA for various gauges or bend radii by a unique vhinge bracket slidable within a sleeve orihousing heldin position by a screw and Ycompressible spring, the spring keeping it in its extended position while the/screw allows 'adjustments `to height and securesY the hinge to the anvil members. The-'axisy of the mandrel and lauxiliaryemvils being the same this will remain thesame-at any setting ofthe screw. This provides for Afree-pivotal action of the mandrel and auxiliary anvil. The greater the bend radius and the thicker 'the metal the further this center axis is moved from 'the-anvil surfaces (like enlarging the centers of aV drafting compass). To make-up*l for various radius bends a mandrel `nose of that radius has to be provided.

With these -and `otherA objects and ladvantages inA view the invention embodies an anvil formed of Aa plurality'of spaced 'sections with mandrel supporting `frames pivotal-ly mounted at the `ends of the anvil and with means for actuating the bending-section of theanvil and mandrel for forming'the edges'of a plate positioned on the anvil in differentV shapes.

Other-features and advantagesk loi the invention will appear lfrom the -following description taken inconnection'with `the drawings wherein:

Figure lis an end'elevational view'of the improved platebendingl tool showing themounting parts of Vthe mandrel andauxiliary 'anvil in lprogressive steps inT-dotted lines;

Figure 2 is a vertical Alongitudinal section through thefplatefbending tool showing-the mandrel in the'plate gripping position.

Figure 2a is a'detail showing a section taken on` lineh2a-2a of Figure z-illustrating a vcross head to which actuating links of the mandrel and bending 'anvil 'are connected to across headV on one-end of the-machina Figure 3 is iavertical `cross section-through the machinetaken '-online- 3-3 of Figure 2.

Figure 4 is a detail-showing one end of the mandrel supportinghead.

Figure '5 is a vertical section through the upper endof the mandrel supporting vhead taken on line 55'01' Figure 2Y and-illustrating the 'lever con-f nections therein.

Figure 6 v-isasimi-lar detail taken on line 6--6 of Figure 2.

Figure '7 is a--vertical-cross sectionthrough the tool taken on `line 1-1 of Figure-2.

Figure 8 is a detail showing `a section `takenY onizlines ,'.ofFi'gure .2.. illustrating .the pivotal connection and showing a section of the mandrel.

Figure 9 is a sectional view taken on line 9-9 of Figure 7 showing the stationary anvil and mandrel adjustable supporting elements.

Figure l is a detail illustrating a slot in the inner edges of blocks I2 and I3 in which the ends 'of mandrel holder I4 are mounted.

Figure l1 is a detail illustrating the mandrel positioned above the plate with the plate resting upon the stationary and auxiliary anvils.

Figure 12 is a similar view showing the mandrel lowered to a position upon the plate.

Figure 13 illustrates the position of bend that has progressed up to approximately 90 degrees by actuating the auxiliary anvil with the mandrel keeping its half-pace and maintaining, its bisecting position.

Figure 14 is a similar view illustrating the progress of bend in which the auxiliary anvil has bent the `flange or edge of the material over and approximately against the surface of the mandrel and at which position the mandrel is made to withdraw automatically.

Figure l is a similar view showing the mandrel withdrawn and the auxiliary anvil completing the bend against the stationary anvil without assistance of the mandrel.

Figure 16 is a cross section through the mandrel and hinge sections showing their relation to the top surfaces of the stationary and auxiliary anvils so that larger radii may be formed by insertion of mandrel noses of the appropriate radii.

Figure 17 is a perspective view looking toward the back of the machine.

Figure 18 is a view similar to that shown in Fig. 17 looking toward the front of the machine.

Referring now to the drawings wherein like reference characters denote corresponding parts the improved plate or sheet bending tool of this invention includes three parallel beams comprising a plurality of stationary anvils I0, auxiliary or coacting anvils II, and a plurality of mandrel sections I2 secured in a slot I3, and a holder I4, stationary tubular casings l5 mounted on flanges I5 of vertically disposed posts I9 and 20.

The stationary anvil I0 is formed with a plurality of sections with slots llbetween the sections, as illustrated in Figures 2 and 8 and these sections are carried by a hollow section or bar IS which extends between the posts I9 and 2U. The ends oi the section I8 are supported by posts I9 and 2U and the superstructure in which the mandrel sections I2 are carried is pivotally supported on the upper ends of the posts by blocks 2I and 22 which are pivotally mounted in bearings 23 and 24 by pins 25 and 26, respectively.

The bearing 23 is provided with a square stem 21 that extends into a tubular casing 28 of the auxiliary anvil II and the stem is adjustably secured in the casing by an adjusting screw 29 that extends through an opening 30 in a head 3 I The screw holds the stem against a spring 32.

The bearing 24 is mounted in a similar manner with a stem 33 thereof mounted in a tubular casing 34 on the opposite end of the anvil II and this is held by an adjusting screw 35 that extends through an opening 35 in a head 31 wherein the stem is held against a spring 38.

The bearings 23 and 24 are supported by arms 39 and 40 which extend upwardly from shanks 4I in tubular casings I5 which are mounted on the flanges I6. The Shanks 4| with the associated parts are similar at both ends of the machine and the same reference characters are, therefore,

mounted in the opening used for both. The shanks 4i are adjustably held in the casings by adjusting screws 43 that extend through heads 44 and the Shanks are resiliently urged upwardly by springs 45.

The upper outer surfaces of the shank 4I and stem 2T at one end of the machine are provided with graduations 46 and 41, respectively to facilitate setting the mandrel and supporting elements in relation to the anvils I0 and I I, respectively. The arm 39 is provided with a stop 48 that is positioned to arrest the downward movement of the block 2l in which one end o the mandrel is supported.

The auxiliary swingable anvil I i is also formed with spaced sections having slots between the sections-and the sections of this anvil are carried on a cross member 4S, the ends of which are secured to the tubular casings 28 and 34 by side plates 5S and 5 I. respectively, which extends from the outer peripheral edge of the cross member 49 to the tubular casing 25, as illustrated by the dotted lines, in Figures 3 and '7.

The plate 50 at the end or the machine is provided with a bracket 52 having an arcuate shoe 53 thereon and a link 54, the lower end of which is slidably mounted in a bearing 55 which is pivotally mounted in the bracket 52 on the pin 56. The lower end of link 54 is provided with a head 5l that rides against the inner surface of the shoe 53, as shown in Figure l `up to a point of bend as shown in Figure i4 where it retires from the shoe permitting continued movement of auxiliary anvil il. The upper end of the link 54 is pivotally mounted on a cross head 58 by a pin 59 on which a supporting link Sil is also pivotally mounted. The lower end of the link Ell is pivotally mounted on a bracket 6I extended outwardly from the casing i5, by a pin 62.

The cross head 53 is slidably mounted on a dove-tailed tongue 53 on the outer surface of the block 2 i. The pin 59 is provided with an opening 64 through which a rod 35 extends and the rod is adjustably set to trip lever 88 as the crosshead 58 moves upward on block 2i. This rod is in the outer end of pin 59 by a set screw 66.

The upper mandrel sections I2 are removably mounted in the slot i3 of the vertically slidable plate Id and the upper ends of the mandrel sections are provided with slots 3l by which they are secured in position by set screws 68, as shown in Figure 3. The nose at the lower end of the mandrel is substantially semi-circular in cross section, the center of the radius thereof Abeing positioned on the center of the radius o the bend of the work.

'l'he upper edge of the plate I4 is formed, as illustrated in Figure 2, and the mandrel I2 is forced downwardly with the jack-knife or toggle acting levers including the lower link or sections i3 and i4 and the upper links or sections i5 and it. The bearing blocks 69 and 10 are positioned in recesses 'H and 'I2 of the blade I4. The toggle levers and links are actuated from the positions shown in full lines to the positions shown in dotted lines by the hand lever 94 when it is desired to elevate the mandrel I2.

, A screw 19, threaded in a projection 8i) extended upwardly irom the plate provides a stop for the lever 'le and link l, and the lever 'i5 and a link i3 are held by the fluid or air pressure cylinder l3| which also provides a shock absorber to hold in check the rapid collapse of the toggle element when it is tripped by the trip lever 88 or hand lever 94. This cylinder 8l can also be used Ving a flange toy resettoggle elements when hooked 'upiwith a source (not shown) oli fluid pressure. The vcylinder 8i is pivotally mounted in slotl im in theblock 2| by a pin 82 andthe outer end is provided with a piston rod 83 which is pivotally connected to the pin-815 lby which the Vlink 'i3 is connected to the lever "55.

The upper end of the lever l5 is connected- 'to a link 85 byv a pin-85 with the pinpositioned in a slot Bf? in the end of the link and theopposite-end of the link is connected to a trip lever 38 by a pin Sii. which lever is released by Contact of rod `lili. This trip lever t3 is pivotally mounted on a pin 88, spanning slot i134 in block 2|.. A

A similar link 9| is pivotally connected -to the upper end of the lever 'I6 by Aa pin Q2 and a link 93 connects the links 85 and 9|, the ends of the link 93 being pivotally mounted on the pins f86 and o2. The outer end of the link si is connected to a hand lever B6 by a pin Soin a slot S6 andthe lever te is pivotally mounted in the block 22 by a pin 9i. A spring st, which provides a cushion for the hand lever sil is attached to the end of the 'block 22 by a screw d.

The ends of the plate ill are slidably mounted in slots lili? and lill in the inner facesV ofthe blocks 2| and 22 and the lends of the plate are resiliently urged upwardly by springs H32 and |63. The upper ends of the blocks 2| and 22 are provided with slots |94 and |25 in which the'trip lever 88 and hand lever 9&3 are positioned, respectively.

Side plates |86 and l'lare provided on 'the sides of the blocks 2| and 22 and the upper edges of the side plates are connected by a channel shaped cap |08. The side plates '|136 and |67 eX- tend from the outer ends of the blocks 2 at one end ofthe machine to the outer ends of the blocks 22 at the opposite end of the machine. |The pins TI and 'i8 on which the levers `'iliand "i5, respectively, are pivotallymounted are supported in the side or cover plates |66 and lill,y as shown in Figure 3. K

The link 73 is pivotally connected to the bearing 69 with a pin 3, and the link M is pivotally connected to the bearing 'i0 with'a pin 4 and to the lever 7S with a pin '5.

The upper movable mandrel and auxiliary anvil may be actuated by hand or other suitable means.

With the parts arranged as shown and described a sheet of material, as indicated by the numeral |09 is placed upon the stationary and auxiliary anvils l0 and with the mandrel in the upwardly extended position, as shown wheremandrel 1s released to positioned at substantially 45 degrecs to the face of the anvil l0, as shown in this movement the auxiliary anvil edge of the blade upwardly formwhich is positioned at right thefsuperstructure.coming to a stop in theiposie tion indicated 'by numeral H2, in Figurel 1i. At

this point two things happen, trip lev'er 88 is contacted by pin 65, whichhas moved outward along block 21 guided byA slid'able Jhead T58 toward trip-:lever 88, Vthereby tripping toggle elements which' automatically withdraw "mandrel `from the forming operation and the head "551 fof link 5l leaves the Farcua'te 'shoe 53 allowing continued movernentof the auxiliary anvil which bends the material downward-Vito la position substantially parallel with the body of the plate between the twowanvil structures as illustrated in Figure 15. By'this rneans a comparatively simple operation bends the 'edge of the plate `upwardly and `over to form fa hem orY bead wherein the ilange lor edg'e of the plate may `be moved through an angle greater than degrees.

*From thefforegoingdescription it will beobvlious lthat an improved plate bending machine is pro ided wherein `a plate, as indicated by the numeral` 109, Yis positioned on stationary Aand movable anvils-lla and as illustrated inFig. 3 and with the mandrel |2 positioned against 'the Il upwardly Figs. 11 yto 15.

which bisects the angle between the forming anvils.

It will be understood that the anvils and mandrel may be provided in diierent shapes and decarried by tubular casings 8 similar to the casing I5.

of the plate, the superstructure is` selection of an interchangeable mandrel I l3--I I4 fitting the form desired.

It will be understood that other modifications may be made in the design and arrangement of the parts without departing from the spirit of the invention.

What is claimed is:

1. A brake comprising spaced vertically disposed posts, a horizontally disposed stationary anvil extended between and connecting the upper ends of the posts, bearings carried by the posts and extended to points whereby the axes of the bearings are aligned with the point of bend of a plate formed by the brake and positioned on the upper surface of the stationary anvil, a coacting anvil having an upper surface in the plane of the upper surface of the stationary anvil and a face positioned in meeting relation with the face of the stationary anvil, a frame positioned above the anvils, means whereby the coacting anvil and frame are pivotally mounted in said bearings extended from the posts and wherein the pivot point of the coacting anvil and frame is in alignment with the axes of the bearings, a mandrel carried by the frame and positioned to engage a plate positioned on the anvils, and means whereby the frame with the mandrel therein is rotated upon rotation of said coacting anvil whereby the mandrel is positioned to bisect the angle between the stationary and coacting anvils.

2. A brake comprising spaced vertically disposed posts, a horizontally disposed stationary anvil extended between and connecting the upper ends of the posts, bearings carried by the posts and extended to points whereby the axis of the bearings are aligned with the point of bend of a plate formed by the brake and posi tioned on the upper surface of the stationary anvil, a coacting anvil having an upper surface in the plane of the upper surface of the stationary anvil and a face positioned in meeting relation with the face of the stationary anvil,

a frame positioned above the anvils, means,

whereby the coacting anvil and frame are pivotally mounted in said bearings extended from the posts and wherein the pivot point of the coacting mandrel and frame is in alignment withA the axes of the bearings, a mandrel carried by the frame and positioned to engage a plate positioned on the anvils, andmeans whereby the frame with the mandrel therein is rotated upon,

rotation of said coacting anvil whereby the mandrel is positioned to bisect the angle between the stationary and coacting anvils, said anvils and mandrel being formed in sections.

3. A brake as described in claim l, wherein the mandrel is Ymounted to slide vertically in the frame and means is provided for urging the mandrel downwardly in clamping relation with a plate on the anvils,

4. In 'a brake as described in claim l, means mounting the mandrel in the frame whereby the mandrel is adapted to slide vertically in the frame, toggle elements mounted in the frame and positioned to coact with the mandrel, and a. hand lever pivotally mounted on the frame for actuating the toggle elements.

5. A brake as described in claim 2, in which the frame includes blocks pivotally mounted in the bearings, and a plate mounted to slide vertically in the blocks with the mandrel sections carried by the plate, and with the plate actuated with a hand lever through toggle elements to clamp a plate on said anvils.

6. A brake as described in claim 2, wherein resilient elements are incorporated in the connections of the bearings to the posts.

7. A brake as described in claim 2, in which the travel of the frame and mandrel is controlled by a link pivotally connected at one end to supporting means on one of said posts and at the other to the frame, and in which the travel of the coacting anvil is controlled by a link, pivotally connected at one end to the frame and at the other, to the coasting anvil.

RAYMOND E. SMITH, Sii.

References Cited in the iile of this patent UNITED STATES PATENTS 

